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Signing UpStep 1Gather your materials
Parts/Materials
• (2) Bearings from inline skates (Search YouTube for vids on how to remove and clean them.)
• (1) Balloon for Bands/tires (Use heavier duty 'punching balloon'.)
• (1) Popsicle/craft stick (I like nice color ones, but use whatever you like.)
• (1) 2 inch piece of 5/16 inch wooden dowel (The dowel should fit snugly into the bearings.)
• (2) Motors (3VDC, Jency Motor ST130-12240-38, Jenco part # 154915 or Mabuchi FK-260SA-10400, Jenco part # 2081908)
• (2) AA alkaline batteries
• (1) QRD-1114 reflective sensor
• (1) bc 337 NPN transistor
• (1) Resistor (50 to 85 ohm for IR emitter)
• (1) Battery holder for 2xAA batteries
• 8 inches of red wire
• 6 inches of white wire
• 6 inches of black wire
Tools/Supplies
• Wire cutters
• Wire strippers
• Needle nose pliers
• Hot glue gun and glue sticks
• Soldering iron and solder
• Drill and 1/16 inch drill bit
• Sharp scissors
• Heat shrink tubing (1/16 inch, 3/32 inch, and 1/8 inch)
• Butane Lighter or other heat source
• (2) Bearings from inline skates (Search YouTube for vids on how to remove and clean them.)
• (1) Balloon for Bands/tires (Use heavier duty 'punching balloon'.)
• (1) Popsicle/craft stick (I like nice color ones, but use whatever you like.)
• (1) 2 inch piece of 5/16 inch wooden dowel (The dowel should fit snugly into the bearings.)
• (2) Motors (3VDC, Jency Motor ST130-12240-38, Jenco part # 154915 or Mabuchi FK-260SA-10400, Jenco part # 2081908)
• (2) AA alkaline batteries
• (1) QRD-1114 reflective sensor
• (1) bc 337 NPN transistor
• (1) Resistor (50 to 85 ohm for IR emitter)
• (1) Battery holder for 2xAA batteries
• 8 inches of red wire
• 6 inches of white wire
• 6 inches of black wire
Tools/Supplies
• Wire cutters
• Wire strippers
• Needle nose pliers
• Hot glue gun and glue sticks
• Soldering iron and solder
• Drill and 1/16 inch drill bit
• Sharp scissors
• Heat shrink tubing (1/16 inch, 3/32 inch, and 1/8 inch)
• Butane Lighter or other heat source
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what will be the changes i would have to do in the circuit if i uses that combination.
please reply soon sir.
Alternately, you could use descrete infrared LED and phototransistors. The QRD1114 is just small versions of these components in a nice case. The case also provides some ambient light filtering.
So if you go with the descrete components, you may want to place a piece of shrink tubing over the phototransistor to help block some of the ambient light.
You would connect them just as shown in the schematic.
As mentioned above,i understand that both QRD1114 & CNY70 packages contain a IR source & a two terminal Photo transistor(or Photo Diode maybe). So, it would be extremely helpful to me if you could mention the individual component number(e.g QRD1114 Reflective Sensor) of the combination of IR source & a two terminal Photo transistor that you say can replace the QRD1114 package.
However, you can often find an IR emitter and detector sold as a pair. You may need to use some shrink tubing to enclose the detector and protect it from interference.
I don't have specific components to recommend, but see what you can find and use Ohm's Law and the values for the IR emitter forward voltage and the voltage of your supply (3V if you use two AA batteries as in this instructable) to calculate an appropriate current limiting resistor.
I have a new instructable with a different version of the SpurtBot. I provide links where you can buy the components for that one.
http://www.instructables.com/id/Introduction-SpurtBot-ShadowRunner
If you hover over the picture in Step 1 of this Instructable, there are some notes on selecting the motors.
when i finished the robot i connect it to the battery just the left one turn and the right one never turn but when i use the 9v battery the 2 motors turn
QRD1114 is not available to me,so can i use one of the following optical reflective sensors as a substitute:
TCRT-5000
RPR 220
Thank You
However, with the 9V battery, I'm concerned you will burn out the CNY70 with too much current. Also, your robot will move much faster with 9V, so it will be harder to keep it on track.
I suggest you go back to 2AA batteries, but reduce the resistor to something like 58ohms. This will make the IR LED brighter by increasing the current for the same voltage. Make sure you use alkaline batteries, not rechargeables. Rechargeables only have about 1.2V each, which will not be enough. Of if your AA batteries were a little worn down, it might not work well. You
If you want to stick with a 9V battery, increase your resistor before you damage your CNY70. Look at the datasheet and you will see the maximum current is 50 mA, but you want to stay well below that. Typical voltage drop is 1.25V, but could be as high as 1.6V.
So let's say it is dropping the max voltage (best case), You subtract this from the battery voltage.
9V - 1.6V = 7.4V
So your resistor has 7.4V across it. Using Ohm's Law (I = V / R) , we can get the current through the resistor and IR LED.
Current (I) = 7.4V / 75 ohms = 0.0987 amps or 98.7 mA.
Way too high, even for the best case.
To pick your resistor, decide on your desired current. Let's try 35mA. Now rearrange the calculation to find the best resistor.
Resistance (R) = 7.4V / 0.035 A = 211.4 ohms. That's not a resistor value you can get, but you can get a 220 ohm resistor.
Remember I said this was 'best case'? If the IR LED only drops its typical 1.25V, will a 220 ohm resistor be safe? Let's see:
Current (I) = (9V - 1.25V) / 220 ohms = 0.03522, = 35.2 mA,
Still safe.
So in summary, either:
1) Go with two new alkaline AA batteries and reduce your resistor to 58 ohms. You could go a little lower. Use the calculations above to figure out how low is safe.
2) Try the 9V with a higher value resistor. 220 ohms should work well. Your robot will go faster so it may not work as well.
The problem both of these devices have is the detection distance. The RPR 220 needs 6mm, and the TCRT-5000 needs 12mm. Compare that to the CNY70, which needs 0.3mm (less than a mm).
Since the SpurtBot uses the detector as its front wheel/slider, the detection distance is critical.
If you want to try it, use the RPR 220, but add a small bead or other object to act as a front wheel. Be sure that the detector rests 6mm above the surface of the floor.
Let me know how it comes out!
As I've said before, the CNY70 should work OK with this design (in fact I know it does). You just have to make some adjustments to the connections. Read through the other comments; there is some good info.
For the motors, if you cannot find the ones I specify, please read the notes on the picture in Step 1. If you hover your mouse over the motors, I provide some guidance on what to look for.
Here's your homework: Go find out what a datasheet is. Google can help you more quickly than I.
Now that you know what a datasheet is, hopefully you are already looking up the datasheets in question and studying them to learn what you need.
I'll even give you some advice. You will usually see something labeled 'Absolute Maximum Ratings' or similar. Don't design to those specifications. For example, if the maximum current rating of the IR LED in the CNY70 is 50mA, you want to operate it well below that.
Look lower down in the datasheet for more ratings that are more typical for normal operations.
One more hint, when you look at the pin diagrams for part, be sure you know if you are looking at the part from the top or from the bottom. That's an easy mistake to make.
SOURCE:http://en.wikipedia.org/wiki/Datasheet
So for example- Pin 4 in QRD1114 is cathode, and pin 2 in CNY70 is cathode. So the connection that goes to pin 4 in this instructable which uses QRD1114 will go to pin 2 if i'm using CNY70.Am i right?
Here are some images:
And yes, you have it correct. Also, keep in mind the image on the right of the CNY70 is the bottom view, as though you are looking down at the pins.
If you are still constructing, here are a few things to try.
1) If you own a digital camera, power on the robot and view the lenses of the sensor through your camera. The camera can see infrared light, even though your eye cannot see it directly. If you see a bluish light coming from the sensor, you know the IR LED is working.
2) The left wheel should always run. The right wheel should only run when the robot's sensor sees a reflection from a bright white surface. If the bc337 transistor is and the sensor are working, the right wheel should turn on when on a white surface, and turn off when on a dark surface or if there is no surface to reflect any IR.
reply please...
thanks :)
the TCRT5000L has a sensing distance of 12mm. There's a diagram in the datasheet that shows this pretty clearly. So you cannot use this device as the front slider for the SpurtBot. You could use a 12mm bead or other round-bottomed object as the slider, and then mount the TCRT5000L just in front or behind the bead.
You will also need to adjust the circuit to get the right amount of current through the IR LED. I think the TCRT5000L wants to operate at a higher current (60 mA max, so maybe aim for 45-50 mA). You increase the current by reducing the value of the resistor. I suggest a 33 ohm resistor.
but what about the connections with the RPR 220? Do they need to change? Sir if it needs to change , sir then please tell me how to do it, as i cannot make changes on my own.
THANK YOU
Study the datasheets for the original part (QRD-1114) and the part you want to use, which you can find with a quick web search. Compare the pin connections. Adjust the design.
I replied to you earlier explaining how to choose the right value for the resistor, depending on the batteries you use and the sensor you select.
Give it a try. You will learn so much by figuring this out on your own.
you mean by pins the anode collector emitter catode i have done some search and i have and i followed your circuit diagram with 75ohm and bc337 npn and a battery of 3v but it dosen't work i have followed this information http://www.google.dz/imgres?imgurl=http://personales.alumno.upv.es/~jobelma2/sensores%2520y%2520motores_archivos/image004.jpg&imgrefurl=http://personales.alumno.upv.es/~jobelma2/sensores%2520y%2520motores.htm&h=345&w=381&sz=14&tbnid=I_DS1YqtGpRgHM:&tbnh=90&tbnw=99&prev=/search%3Fq%3Dcny70%26tbm%3Disch%26tbo%3Du&zoom=1&q=cny70&docid=tvkP6Lp7Ml4wNM&hl=fr&sa=X&ei=v4CmT9rEKpGYOuXb_J4D&sqi=2&ved=0CHoQ9QEwBA&dur=113
i don't know wht is the probleme because im not good in electronic im young siir please help me
I'll give you some advice on troubleshooting the CNY70. If you have a digital camera, turn on the SpurtBot and look at the lens of the CNY70 through the camera. Unlike the human eye, a digital camera can detect the IR light that the CNY70 emits. If you can't see any light through a digital camera, chance are you don't have it connected correctly, or that you blew the device earlier by connecting it without a current limiting resistor.
Then follow the instructions, but adjust the connections to the CNY70 so that the resistor, wires and pins from the transistor go to the correct pins. I will not provide you a circuit diagram, but with a little research and thinking on your part you should be able to get the CNY70 working with this robot.
Good luck!
I can't find the QRD114 but CNY70 is available to me.What should I do further?Do i follow the instructions after that as it is or i have to make any modifications?By the way a very excellent concept! Keep it up!
PLEASE DO REPLY!
You will have to adjust the way you connect the resistor, wires and pins from the transistor to the CNY70, since its pins are arranged differently than the QRD1114.
I need the exact model numbers of the devices, or better yet a link to the datasheets for them. I cannot see from the pictures what these devices are.
You are drifting fairly far away from the design of the SpurtBot, so I am not promising you anything. Let me know what the devices are and I'll see what I can recommend.
http://www.societyofrobots.com/schematics_infraredemitdet.shtml
1) You will need to select R1 and R2 based on the 3V supply of the SpurtBot.
2) You will also need to reverse the postions of R2 and the phototransistor. This way, when the phototransistor sees a reflection from a white surface, it will turn on and send a positive voltage to Vout. Vout would connect to the base of the bc337 transistor.
http://www.roboticsconnection.com/p-80-single-line-following-sensor.aspx